The present invention relates to a hydraulic anti-skid apparatus for use in a vehicle braking system between a master cylinder and a wheel brake cylinder, and more particularly to a hydraulic anti-skid apparatus of the type which comprises a cut-off valve disposed within a braking circuit connecting the master cylinder to the wheel brake cylinder, a bypass valve disposed within a bypass passage of the braking circuit, and first and second pistons respectively arranged to control opening and closing operations of the cut-off valve and the bypass valve.
Such a conventional hydraulic anti-skid apparatus as described above has been proposed, for example, in the Japanese Patent Early Publication 58-199258, wherein a main body for the anti-skid apparatus is formed therein with two parallel cylinders respectively to contain the cut-off valve and the associated first piston and to contain the bypass valve and the associated second piston. In such a construction of the anti-skid apparatus, the component parts of the cut-off valve and the first piston are assembled within one of the cylinders the one end of which is closed by a closure member, and further the component parts of the bypass valve and the second piston are assembled within the other cylinder the one end of which is closed by another closure member. Furthermore, it is necessary to form a communication passage between the cylinders during the manufacturing process of the main body. For these reasons, the conventional anti-skid apparatus is large in size and complicated in construction, resulting in a decrease in its productivity.